Date: Thu, 26 Sep 2013 12:32:47 -0700
Message-ID: <CAGN7qDD-=yoo3x8mDy58yYSouEvDdwg9MwTzDGPSB_LJpvYr1A@mail.gmail.com>
To: Brad Kemper <brad.kemper@gmail.com>
Cc: Henrik Andersson <henke@henke37.cjb.net>, Chris Lilley <chris@w3.org>, "Tab Atkins Jr." <jackalmage@gmail.com>, Simon Sapin <simon.sapin@exyr.org>, www-style list <www-style@w3.org>
It's weird that it works like that, right? See attached png and PDF. The intersection of a 100% cyan rect and a 100% magenta rect at 50% alpha is 50% cyan and 50% magenta. On Thu, Sep 26, 2013 at 7:47 AM, Brad Kemper <brad.kemper@gmail.com> wrote: > > > On Sep 26, 2013, at 4:35 AM, Henrik Andersson <henke@henke37.cjb.net> > wrote: > > > > Rik Cabanier skriver: > >> > >> 5. How to handle content that has an RGB only operation (such as a > >> colormatrix filter) during export to CMYK > > > > Wouldn't that particular filter make just as much sense as per channel > > blend modes? After all, it is a per channel operation. Kinda. > > > > It would obviously need a dedicated configuration for other color > > spaces, but the operation itself should make sense. > > > > Question is, has anyone actually tried using a color matrix on anything > > besides RGB? Not counting shenanigans to setup the matrix to convert to > > rgb before the main effect... > > I don't know much about the colormatrix filter, but for something like > 'opacity', I don't see how you wouldn't convert cmyk to rgb before mixing > channels. One is subtractive color and the other is additive.
(image/png attachment: alpha-cmyk.png)
- application/pdf attachment: alpha-cmyk.pdf